While new research suggests that testosterone therapy could be used to treat depression in men, some experts are urging the use of caution in interpreting those results.

In a study published in JAMA Psychiatry on November 14, German researchers report that testosterone replacement therapy was linked to a significant reduction in symptoms of depression among men, particularly among those who received higher doses.

According to the findings, men who took testosterone therapy were more than twice as likely to report a decrease in the symptoms of depression than men given a placebo. But the researchers warned that the studies they reviewed were never really meant to specifically examine testosterone’s effects on depression.

“Testosterone treatment appears to be effective and efficacious in reducing depressive symptoms in men, particularly when higher-dosage regimens were applied in carefully selected samples,” the researchers concluded. “However, given the heterogeneity of the included RCTs, more preregistered trials are needed that explicitly examine depression as the primary end point and consider relevant moderators.”

In an editorial published alongside the study’s findings, Shalendar Bhasin of Harvard Medical School and Brigham and Women’s Hospital in Boston, and Dr. Stuart Seidman from Columbia University in New York, warned that the findings do not include enough high quality evidence to say that testosterone therapy can be used to treat depression with any confidence.

“Although this meta-analysis adds to the body of data that testosterone administration may be associated with small improvements in depressive symptoms, we do not know whether these improvements are clinically meaningful,” they wrote. “Furthermore, neither the long-term safety nor the efficacy of testosterone therapy has been established in any depressive disorder. Because some of the adverse effects of testosterone are associated with its dose and on-treatment concentrations, the use of supraphysiologic doses of testosterone could be associated with increased risk of adverse effects and is currently not recommended.”

Testosterone Side Effects

The findings come following years of concerns that drugs have been over-marketed to men without any real medical need for the treatments, after findings that side effects of the low testosterone drugs may increase the risk of heart attacks, strokes and sudden death for men.

While medications like Androgel, Testim and others were originally intended as a “niche” treatment for men suffering from confirmed testosterone deficiency, amid aggressive marketing over the last decades, the drugs grew to generate billions in annual sales.

There are currently more than 6,000 Androgel lawsuits and other claims pending against makers of testosterone replacement therapy, alleging that users and the medical community were not adequately warned about the potential health risks, including an increased risk of heart attack, stroke, pulmonary embolism, deep vein thrombosis, blood clots and other life-threatening health problems.